1. Field of the Invention
This invention relates to an electric oven toaster broiler and, more particularly, to an improved readily manufacturable cam control mechanism for such an oven toaster broiler.
2. Description of the Prior Art
In a prior pending application, Ser. No. 06/490,407, filed May 2, 1983, now U.S.Pat. No. 4,456,820 to Charles Z. Krazsnai and Paul V. Snyder, assigned to the same assignee as the present invention, there is disclosed a rotatable cam control mechanism for an oven toaster broiler. As shown a rotatable cam 50 is provided for setting the threshold temperature of a thermostat switch 32, 81, 83 during baking, toasting and broiling operations. A circular disc portion 92 of the cam extends rearwardly and is in sliding engagement with a thermostat cam follower 84 so that the rotary position of the cam 50 may be manually adjusted to set the disc portion 92 of the cam to set the thermostat cam follower 84 for a particular toast color. The disc portion 92 of the cam also includes a sloping cam surface for setting bake temperatures from 200.degree. to 500.degree. during a baking operation. In addition, the disc portion 92 of the cam includes a rearwardly extending surface for setting a very high threshold temperature for the thermostat switch 32 during a broiling operation. Thus, the rotary disc portion 92 of the cam operates on the cam follower 84 to set the position of the thermostat switch contact 83 during a toasting, broiling, or baking operation.
As shown more particularly in FIG. 8 of the pending patent application, the thermostat switch 32 includes a lower contact 81 which is fixed to a blade 82 that may be moved forwardly and downwardly by a rod 42 upon an increase in temperature in the toaster oven and an upper rearward settable contact 83. The temperature setting of the thermostat switch 32 is adjusted or set by means of the aforementioned cam follower blade 84 that extends a substantial distance to the right from a mounting block to which it is fixed. An adjusting screw 88 is connected to the free end of the cam follower blade 84 for cooperating with a switch block 90 formed of insulating material to adjust the position of the switch contact 83. Contact 83 is fixed to a blade 85 and the insulating block 90 is connected to blade 85. Accordingly, when the desired temperature within the oven toaster has been achieved, a bi-metal sensor 40 moves rod 42 forwardly to move switch contact 81 forwardly away from contact 83 to open switch 32.
As shown in FIG. 3 of the co-pending patent application, the bi-metal sensor 40 is mounted on a bracket which is connected to a mounting block 66 that is spaced somewhat to the right of the mounting for cam follower blade 84.
In the prior art construction shown in the pending patent application, the adjusting screw 88 that is connected to the free end portion of the cam follower blade 84 is positioned relatively close to the portion of the cam follower 84 that is in sliding contact with the disc portion 92 of the cam and a substantial distance away from the left fixed end portion of the cam follower blade 84 so that the cam surface 92 is made with a slight incline to move the sliding portion of the cam follower about the same distance rearwardly as it is desired to move the adjusting screw 88 rearwardly to set the position of switch contact 83.
Our invention is concerned with such an oven toaster control mechanism and, more particularly, to an improved, lower cost, more reliable cam and cam follower construction and mounting arrangement.